Hi all,
I am hoping to glean some experience from you guys regarding the best shock sensor to implement for a soccer/football game. I plan to have a white heavy fabric screen onto which I will project an image of a penalty kick. A people will kick a soccer ball against the screen and this will trigger a little video to be played of the ball going into the nets. However, I need to use a shock sensor on the back of the screen and I have no idea what is best in terms of robustness, size of shock, etc.
I guess most sensors are tuned to detect small shocks, but I need a sensor to detect a soccer ball hitting any part of the screen, but at the same time not being set off every time someone opens a door and the screen sways.
All advice from you guys is gratefully received.
Thanks,
George

 

You can use a strain guage bridge circuit, but it would ideally need to be on a hard surface. Alternatly a piezo sensor would work, but it would just pick up vibrations.

 

A cheap piezo disc gets my vote. You would need to condition its output signal to prevent spurious triggering of the video.

 

An accelerometer or even a microphone would probably do it. The advantage of an accelerometer is it would give some idea of how hard the ball had been kicked if that is of interest.

 

Don't you need to detect the ball strike position too so that the video shows the ball in the same path as the kicked ball was? It look pretty silly/cheap if it didn't IMO..

And I would look at how "golfing" screens accomplish the same exact task.

 

The force of a soccer ball is probably enough to trigger a microswitch. Problem: If the ball only has enough velocity to barely roll into the goal area, that's a goal, but it won't trigger a microswitch.

 

I presume that the screen is supported by springs at the four corners. I would use a seismometer at one corner. A small speaker with a small weight attached at the center works. Cell phone speaker might be a bit fragile. High Z also better.
Maybe a tilt switch would work, nice and rugged, could have one at each corner. For # 12's rolling ball add a beam break ckt.